Griffin M E, Dimitriadis E, Lenehan K, Owens D, Collins P, Johnson A, Tomkin G H
Department of Diabetes and Endocrinology, Adelaide Hospital, Dublin, Ireland.
QJM. 1996 Mar;89(3):211-6. doi: 10.1093/qjmed/89.3.211.
Alterations in low-density lipoprotein (LDL) composition in diabetes affect its function with respect to control of de novo cholesterol synthesis. We examined the effect of 4 weeks of an oleic-acid-rich diet on LDL composition and function in eight Type 2 diabetic and eight non-diabetic control subjects. LDL (density 1.019-1.063 g/l) was isolated by sequential ultracentrifugation. LDL composition was measured and LDL fatty acids were determined by gas liquid chromatography. Cholesterol synthesis was measured by [14C]-acetate incorporation into the freshly isolated mononuclear leucocytes. Fasting blood glucose fell from 9.3 +/- 2.0 to 8.2 +/- 1.2 mmol/l (p < 0.05) and fasting serum insulin increased from 8.3 +/- 2.8 to 10.4 +/- 5.0 mIU/l (p > 0.05) in the diabetic patients. LDL oleic acid increased in the diabetic patients from 18.8 +/- 1.8% to 22.5 +/- 1.9% (p < 0.01) and in the non-diabetic subjects from 19.9 +/- 1.8% to 23.3 +/- 2.8% (p < 0.01). The LDL-esterified to free cholesterol ratios of 3.0 +/- 0.6 and 2.7 +/- 0.2 for the diabetic and non-diabetic patients were similar, and decreased significantly (p < 0.01) to 2.4 +/- 0.5 and 2.2 +/- 0.4, respectively. Baseline [14C]-acetate incorporation was similar in the two groups, and decreased after diet from 437 +/- 239 to 249 +/- 144 ng/g cell protein (p < 0.05) in the diabetic patients. There was a negative correlation between the LDL-esterified to free cholesterol ratio and the ratio of oleic to linoleic acid in the LDL (r = -0.39, p < 0.05) and a negative correlation between fasting blood glucose and LDL oleic acid in the diabetic patients (r = -0.51, p < 0.05). Enrichment of LDL with oleic acid appears to improve its ability to regulate endogenous cholesterol synthesis in both control and diabetic subjects. In the diabetic population, the diet had a favourable effect on glycaemic control.
糖尿病患者低密度脂蛋白（LDL）成分的改变会影响其在从头合成胆固醇控制方面的功能。我们研究了富含油酸的饮食4周对8名2型糖尿病患者和8名非糖尿病对照者LDL成分及功能的影响。通过连续超速离心法分离LDL（密度1.019 - 1.063 g/l）。测量LDL成分，并用气相色谱法测定LDL脂肪酸。通过将[14C] - 乙酸掺入新鲜分离的单核白细胞中来测量胆固醇合成。糖尿病患者空腹血糖从9.3±2.0 mmol/l降至8.2±1.2 mmol/l（p < 0.05），空腹血清胰岛素从8.3±2.8 mIU/l升至10.4±5.0 mIU/l（p > 0.05）。糖尿病患者LDL油酸从18.8±1.8%增至22.5±1.9%（p < 0.01），非糖尿病受试者从19.9±1.8%增至23.3±2.8%（p < 0.01）。糖尿病患者和非糖尿病患者的LDL酯化胆固醇与游离胆固醇比值分别为3.0±0.6和2.7±0.2，相似，且分别显著降至2.4±0.5和2.2±0.4（p < 0.01）。两组的基线[14C] - 乙酸掺入相似，糖尿病患者饮食后从437±239降至249±144 ng/g细胞蛋白（p < 0.05）。LDL酯化胆固醇与游离胆固醇比值与LDL中油酸与亚油酸比值呈负相关（r = -0.39，p < 0.05），糖尿病患者空腹血糖与LDL油酸呈负相关（r = -0.51，p < 0.05）。LDL中富含油酸似乎能改善其在对照者和糖尿病患者中调节内源性胆固醇合成的能力。在糖尿病患者群体中，该饮食对血糖控制有有利影响。
